/*    Copyright 2014 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

#include "mongo/platform/basic.h"

#include "mongo/logger/log_component.h"

#include <boost/static_assert.hpp>

#include "mongo/base/init.h"
#include "mongo/util/assert_util.h"

namespace mongo {
namespace logger {

namespace {

// Component dotted names.
// Lazily evaluated in LogComponent::getDottedName().
std::string _dottedNames[LogComponent::kNumLogComponents+1];

    /**
     * Returns StringData created from a string literal
     */
    template<size_t N>
    StringData createStringData(const char (&val)[N]) {
        return StringData(val, StringData::LiteralTag());
    }

    //
    // Fully initialize _dottedNames before we enter multithreaded execution.
    //

    MONGO_INITIALIZER_WITH_PREREQUISITES(SetupDottedNames, MONGO_NO_PREREQUISITES)(
            InitializerContext* context) {

        for (int i = 0; i <= int(LogComponent::kNumLogComponents); ++i) {
            logger::LogComponent component = static_cast<logger::LogComponent::Value>(i);
            component.getDottedName();
        }

        return Status::OK();
    }

}  // namespace

// Children always come after parent component.
// This makes it unnecessary to compute children of each component
// when setting/clearing log severities in LogComponentSettings.
#define DECLARE_LOG_COMPONENT_PARENT(CHILD, PARENT) \
    case (CHILD): \
        do { \
            BOOST_STATIC_ASSERT(int(CHILD) > int(PARENT)); \
            return (PARENT); \
        } while (0)

    LogComponent LogComponent::parent() const {
        switch (_value) {
        case kDefault: return kNumLogComponents;
        DECLARE_LOG_COMPONENT_PARENT(kJournaling, kStorage);
        case kNumLogComponents: return kNumLogComponents;
        default: return kDefault;
        }
        invariant(false);
    }

    StringData LogComponent::toStringData() const {
        switch (_value) {
        case kDefault: return createStringData("default");
        case kAccessControl: return createStringData("accessControl");
        case kCommands: return createStringData("commands");
        case kIndexing: return createStringData("indexing");
        case kNetworking: return createStringData("networking");
        case kQuery: return createStringData("query");
        case kReplication: return createStringData("replication");
        case kSharding: return createStringData("sharding");
        case kStorage: return createStringData("storage");
        case kJournaling: return createStringData("journaling");
        case kWrites: return createStringData("writes");
        case kGeo: return createStringData("geo");
        case kNumLogComponents: return createStringData("total");
        // No default. Compiler should complain if there's a log component that's not handled.
        }
        invariant(false);
    }

    std::string LogComponent::getShortName() const {
        return toStringData().toString();
    }

    std::string LogComponent::getDottedName() const {
        // Lazily evaluate dotted names in anonymous namespace.
        if (_dottedNames[_value].empty()) {
            switch (_value) {
            case kDefault: _dottedNames[_value] = getShortName(); break;
            case kNumLogComponents: _dottedNames[_value] = getShortName(); break;
            default:
                // Omit short name of 'default' component from dotted name.
                if (parent() == kDefault) {
                    _dottedNames[_value] = getShortName();
                }
                else {
                    _dottedNames[_value] = parent().getDottedName() + "." + getShortName();
                }
                break;
            }
        }
        return _dottedNames[_value];
    }

    StringData LogComponent::getNameForLog() const {
        switch (_value) {
        case kDefault:              return createStringData("-       ");
        case kAccessControl:        return createStringData("ACCESS  ");
        case kCommands:             return createStringData("COMMANDS");
        case kIndexing:             return createStringData("INDEXING");
        case kNetworking:           return createStringData("NETWORK ");
        case kQuery:                return createStringData("QUERY   ");
        case kReplication:          return createStringData("REPLSETS");
        case kSharding:             return createStringData("SHARDING");
        case kStorage:              return createStringData("STORAGE ");
        case kJournaling:           return createStringData("JOURNAL ");
        case kWrites:               return createStringData("WRITES  ");
        case kGeo:                  return createStringData("GEO     ");
        case kNumLogComponents:     return createStringData("TOTAL   ");
        // No default. Compiler should complain if there's a log component that's not handled.
        }
        invariant(false);
    }

    std::ostream& operator<<(std::ostream& os, LogComponent component) {
        return os << component.getNameForLog();
    }

}  // logger
}  // mongo
